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T O P I C R E V I E W

Space Cadet Carl

There have been numerous reports over the last 50 years that the sound waves from the very first Saturn V launch (Apollo 4) broke windows miles away from Launch Complex 39. The assertion is that all of the water suppression systems were not completely installed by the time of the launch in November 1967.

Are these reports true or false?

Jim Behling

There was no sound suppression system for Saturns and if there was, it would have no effect outside the pad area:

The water system was cooling and fire suppression.

The shuttle sound suppression system was to protect the vehicle from reflected sound off the MLP after it climbed a few hundred fleet. Water was also used for SSME start GH2 suppression. And SRB ignition overpressure protection was added after STS-1.

All of this did not reduce the sound created by the vehicle that would be transmitted all around. The peak sound would be when the vehicle was airborne away from effects of the pad.

Cozmosis22

So, am guessing that the whole "broken windows thing" from the early Saturn V liftoff is what we would now call an urban legend?

Robert Pearlman

From a Nov. 16, 1967 New York Times article (cited in an related thread from 2010):

Only then did the shockwave reach the press site 16,000 feet away, traveling through the ground and the air. Staccato bursts, rapid and thunderous, shook the small wooden grandstand, rattled its corrugated iron roof and pushed in the plate glass window on the Columbia Broadcasting System's new mobile studio...

Engineers estimated the noise reached about 120 decibels at the press site, the equivalent of a piston-engine airplane warming up only a few feet away. The "threshold of pain" for loud noises, they said, was 135 to 140 decibels.

Space Cadet Carl

Thanks for the responses. I was on the NASA Causeway for STS-135 and it wasn't anywhere near as loud as I thought it would be. Of course, the causeway is six miles from the pad, as opposed to the VIP press site which is only three miles away.

Jim Behling

Weather conditions such as humidity and wind have an effect on the the sound.

star61

I was on NASA causeway for STS-26 and remember yelling with everyone else and barely able to hear my own voice!

Nothing quite like a Saturn V of course, but certainly loud.

Tony Guidry

I have to agree with Jim Behling that weather did have a significant effect on the sound of a space shuttle launch, regardless of your viewing location.

Over the years, we viewed three launches from, essentially, the same general area in Titusville, along the waterfront (about 12 miles due west of LC-39, "as the crow flies"). All the launches were during the summer months (July/August).

The first launch, in the early '90s, was exceptionally loud, more than I had expected, even at the distance we were from the Pad. The second launch, in 2007, was still moderately loud, but noticeably less than the first one. Finally, the third launch, in 2009, was somewhat of a disappointment, with a rather muffled sound of much lower intensity. I suspect that the winds, the temperature and the humidity were all factors in the variations of the sound.